buttercream transfer last? I have a ton of it left and I did stick it in the fridge...I hope a little while, I don't have another cake to make like that!
I've kept mine in the fridge for a couple weeks or you can freeze the icing and reuse, I've done that also. Try it.
I always seem to over estimate my frosting when I make FBCT. I would rather have too much than not enough of a color! I keep mine in the frig for serveral weeks also with no harm. I have never frozen it before but I think I will in the future. That way I will stop eating the leftovers!!!